In South Africa, the country with the highest burden of HIV infection in the world, men either fail to access or drop out early from the 'cascade' of HIV testing, treatment and care at considerably higher rates than women. Linking men to care earlier, and keeping them retained and adherent for longer, will improve not only their own health, but will also directly translate into a range of better health outcomes for their partners, families and communities. There are many reasons men drop out of the HIV cascade but two critical factors are 1) the fragmentation within the health system across its various HIV-related services, and 2) a persistent gap between health system- and community-based efforts to support those living with-or trying to avoid-HIV infection. Few interventions exist, especially for men, to address these two critical gaps. This project-Using Information to Align Services and Link and Retain Men in the HIV Cascade-or 'i-ALARM', seeks to 'raise the alarm' about this under-recognized but urgent need, and to develop ways of using health information to more effectively coordinate the work of health system and community service providers. Its specific aims are 1) to understand the performance of the existing HIV cascade for men, and determine the factors affecting the scale and pace of men's movement through this cascade, 2) to develop a health information management (HIM) intervention that brings clinic and community-based providers together to improve the performance of this cascade, and 3) to pilot this intervention and evaluate in what ways it a) improves communication and coordination among clinic and community services, b) leads to changes in service design and delivery, and c) improves men's linkage to and retention in HIV care. To achieve Aim 1, we will conduct a mixed methods study of the local HIV cascade for men in a Cape Town health sub-district using qualitative formative research and a cohort study with retrospective and prospective cohorts. To achieve Aim 2, we will consult with health information and management experts to develop the HIM intervention and work with clinic and community providers already working together in a Cape Town community to establish a 'Men's Linkage and Retention in Care Task Team' (LRTT). In Aim 3, we will support the LRTT in piloting the HIM intervention and conduct an evaluation of this pilot, using both a mixed methods process evaluation of the pilot and an outcomes evaluation using the findings from the prospective cohort study begun in Aim 1. This project is innovative for not only using the HIV cascade as an overarching conceptual framework, but for operationalizing it concretely in an intervention that brings clinic and community stakeholders together to catalyze coordination of their efforts to link and retain men in care. We expect i-ALARM will produce a working model-up-scalable and transferable to other health problems and settings-for how health information management between clinic and community stakeholders can produce innovative and sustainable responses to critical public health needs.